const Crypto = {};

(function(){

var base64map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";


// Crypto utilities
var util = Crypto.util = {

	// Bit-wise rotate left
	rotl: function (n, b) {
		return (n << b) | (n >>> (32 - b));
	},

	// Bit-wise rotate right
	rotr: function (n, b) {
		return (n << (32 - b)) | (n >>> b);
	},

	// Swap big-endian to little-endian and vice versa
	endian: function (n) {

		// If number given, swap endian
		if (n.constructor == Number) {
			return util.rotl(n,  8) & 0x00FF00FF |
			       util.rotl(n, 24) & 0xFF00FF00;
		}

		// Else, assume array and swap all items
		for (var i = 0; i < n.length; i++)
			n[i] = util.endian(n[i]);
		return n;

	},

	// Generate an array of any length of random bytes
	randomBytes: function (n) {
		for (var bytes = []; n > 0; n--)
			bytes.push(Math.floor(Math.random() * 256));
		return bytes;
	},

	// Convert a string to a byte array
	stringToBytes: function (str) {
		var bytes = [];
		for (var i = 0; i < str.length; i++)
			bytes.push(str.charCodeAt(i));
		return bytes;
	},

	// Convert a byte array to a string
	bytesToString: function (bytes) {
		var str = [];
		for (var i = 0; i < bytes.length; i++)
			str.push(String.fromCharCode(bytes[i]));
		return str.join("");
	},

	// Convert a string to big-endian 32-bit words
	stringToWords: function (str) {
		var words = [];
		for (var c = 0, b = 0; c < str.length; c++, b += 8)
			words[b >>> 5] |= str.charCodeAt(c) << (24 - b % 32);
		return words;
	},

	// Convert a byte array to big-endian 32-bits words
	bytesToWords: function (bytes) {
		var words = [];
		for (var i = 0, b = 0; i < bytes.length; i++, b += 8)
			words[b >>> 5] |= bytes[i] << (24 - b % 32);
		return words;
	},

	// Convert big-endian 32-bit words to a byte array
	wordsToBytes: function (words) {
		var bytes = [];
		for (var b = 0; b < words.length * 32; b += 8)
			bytes.push((words[b >>> 5] >>> (24 - b % 32)) & 0xFF);
		return bytes;
	},

	// Convert a byte array to a hex string
	bytesToHex: function (bytes) {
		var hex = [];
		for (var i = 0; i < bytes.length; i++) {
			hex.push((bytes[i] >>> 4).toString(16));
			hex.push((bytes[i] & 0xF).toString(16));
		}
		return hex.join("");
	},

	// Convert a hex string to a byte array
	hexToBytes: function (hex) {
		var bytes = [];
		for (var c = 0; c < hex.length; c += 2)
			bytes.push(parseInt(hex.substr(c, 2), 16));
		return bytes;
	},

	// Convert a byte array to a base-64 string
	bytesToBase64: function (bytes) {

		// Use browser-native function if it exists
		if (typeof btoa == "function") return btoa(util.bytesToString(bytes));

		var base64 = [],
		    overflow;

		for (var i = 0; i < bytes.length; i++) {
			switch (i % 3) {
				case 0:
					base64.push(base64map.charAt(bytes[i] >>> 2));
					overflow = (bytes[i] & 0x3) << 4;
					break;
				case 1:
					base64.push(base64map.charAt(overflow | (bytes[i] >>> 4)));
					overflow = (bytes[i] & 0xF) << 2;
					break;
				case 2:
					base64.push(base64map.charAt(overflow | (bytes[i] >>> 6)));
					base64.push(base64map.charAt(bytes[i] & 0x3F));
					overflow = -1;
			}
		}

		// Encode overflow bits, if there are any
		if (overflow != undefined && overflow != -1)
			base64.push(base64map.charAt(overflow));

		// Add padding
		while (base64.length % 4 != 0) base64.push("=");

		return base64.join("");

	},

	// Convert a base-64 string to a byte array
	base64ToBytes: function (base64) {

		// Use browser-native function if it exists
		if (typeof atob == "function") return util.stringToBytes(atob(base64));

		// Remove non-base-64 characters
		base64 = base64.replace(/[^A-Z0-9+\/]/ig, "");

		var bytes = [];

		for (var i = 0; i < base64.length; i++) {
			switch (i % 4) {
				case 1:
					bytes.push((base64map.indexOf(base64.charAt(i - 1)) << 2) |
					           (base64map.indexOf(base64.charAt(i)) >>> 4));
					break;
				case 2:
					bytes.push(((base64map.indexOf(base64.charAt(i - 1)) & 0xF) << 4) |
					           (base64map.indexOf(base64.charAt(i)) >>> 2));
					break;
				case 3:
					bytes.push(((base64map.indexOf(base64.charAt(i - 1)) & 0x3) << 6) |
					           (base64map.indexOf(base64.charAt(i))));
					break;
			}
		}

		return bytes;

	},




	HMAC : function (hasher, message, key, options) {
 
        // Allow arbitrary length keys
        key = key.length > 16 * 4 ?
              hasher(key, { asBytes: true }) :
              Crypto.util.stringToBytes(key);
 
        // XOR keys with pad constants
        var okey = key,
            ikey = key.slice(0);
        for (var i = 0; i < 16 * 4; i++) {
            okey[i] ^= 0x5C;
            ikey[i] ^= 0x36;
        }
 
        var hmacbytes = hasher(Crypto.util.bytesToString(okey) +
                               hasher(Crypto.util.bytesToString(ikey) + message, { asString: true }),
                               { asBytes: true });
        return options && options.asBytes ? hmacbytes :
               options && options.asString ? Crypto.util.bytesToString(hmacbytes) :
               Crypto.util.bytesToHex(hmacbytes);
 
    },
    sha11:function(k) {
            var u = Crypto.util.stringToWords(k),
            v = k.length * 8,
            o = [],
            q = 1732584193,
            p = -271733879,
            h = -1732584194,
            g = 271733878,
            f = -1009589776;
            u[v >> 5] |= 128 << (24 - v % 32);
            u[((v + 64 >>> 9) << 4) + 15] = v;
            for (var y = 0; y < u.length; y += 16) {
                    var D = q,
                    C = p,
                    B = h,
                    A = g,
                    z = f;
                    for (var x = 0; x < 80; x++) {
                            if (x < 16) {
                                    o[x] = u[y + x]
                            } else {
                                    var s = o[x - 3] ^ o[x - 8] ^ o[x - 14] ^ o[x - 16];
                                    o[x] = (s << 1) | (s >>> 31)
                            }
                            var r = ((q << 5) | (q >>> 27)) + f + (o[x] >>> 0) + (x < 20 ? (p & h | ~p & g) + 1518500249 : x < 40 ? (p ^ h ^ g) + 1859775393 : x < 60 ? (p & h | p & g | h & g) - 1894007588 : (p ^ h ^ g) - 899497514);
                            f = g;
                            g = h;
                            h = (p << 30) | (p >>> 2);
                            p = q;
                            q = r
                    }
                    q += D;
                    p += C;
                    h += B;
                    g += A;
                    f += z
            }
            return [q, p, h, g, f]
    },
    SHA1 : function(e, c) {
            var d = Crypto.util.wordsToBytes(Crypto.util.sha11(e));
            return c && c.asBytes ? d: c && c.asString ? Crypto.util.bytesToString(d) : Crypto.util.bytesToHex(d)
	}
	






};

// Crypto mode namespace
Crypto.mode = {};

})();

module.exports = Crypto;